Method of making refractory brick.



fired material is ground and made into UNITED STATES PATENT OFFICE.

HENRY NOEL POTTER, or NEW RooHELLE, NEW YORK, AssieNoe To GEORGEWESTINGHOUSE, or PITTSBURG, PENNSYLVANIA.

METHOD OF MAKING REFRACTORY BRICK;

Specification of Letters Patent.

Patented Aug. 28, 1906.

To all whom, it may concern.-

Be it known that I, HENRY NOEL POTTER,

.a citizenof the United States, and a resident of New Rochelle, in thecounty of Westchester and State of New York, have invented. certain newand useful Improvements in Methods of Making Refractory Brick, -of whichthefollowing is a specification.

The object of my present invention is to produce a highly refractorybasic or acid brick from materials of reasonable cost.

The most refractory material answering these requirements for basicbrick is doubtless magnesium oxid. This material, however, as is wellknown, becomes progressively denser 'as it is heated to higher andhigher temperatures, reaching its maximum density only when fused. Forthis reason it has been impossible hitherto to produce a brick of thismaterial which would not crack when subjected to uneven heating. Forexample, it has been found that when an attempt is made to produce abrick from the light impalpable powder known as light magnesia it has nobinding powerand cracks to pieces when an attempt is made to fire it.

If the brick, it will also crack up as soon as it is again fired. If,however, the material is first melted and then ground and formed andheated short of fusion, I have found that a brick can be producedthrough the creation of crystals of magnesia. This action is due to thefact that magnesia sublimes below its melting-point. By causing some ofthe magnesia to sublime in this manner I find it possible to get themagnesia into an extremely stron state, and I find also that it does notshrin appreciably even when heated hot enough to give a distinctlycrystalline fracture.

. An acid brickof a highly refractory nature be made by a similarprocess from fused silica. I have discovered, for example, that if fusedsilica be ground to a powder this" powder may be pressed into brick,which is very fragile if no binder is added, but which may be madestrong enough to handle by the addition oftwo per cent. or more ofbinding material, such as starch or tragacanth, which. subsequentlyburns out, leaving the pure amolglphoussilica. dere If now this brick ofpowvitrified silica be heated hot enough to brick particles will arefractory strucone or more sides by fusing the surface.

Bricks of this character have the quality of not cracking when subjectedto sudden changes of temperature or to greater temperature on one sidethan on the other, and are therefore well adapted to use in all placeswhere acid brick is applicable.

While I have spoken of brick in the foregoing" specification, I wish itto be understood as referring to any structure in which highlyrefractory bodies are useful either singly or in combination with othersof like form. For

example, the term should be understood cause some of the silica tosublime slightly, i

broadly enough to include a crucible wherein substances includin thecrucible itself are liable to be subjected to considerable heat.

I claim as my invention 1. The method of producing -ceramic brick, whichconsists in fusing refractory material, cooling, comminuting, formingand submitting it to a temperature high enough to cause it to partiallysublime.

' 2. The method of producing ceramic brick, which consists in fusingrefractory material, cooling, comminuting, forming to the desired shapewith thehelp of a transient binder, and submittingit to a temperaturehigh enough to cause it to partially sublime. 3. The method of producingrefractory brick which consists in shrinking the refractory materialfrom which the brick is to be formed, grinding the shrunk material to apowder, pressing the powder into shape, and heating the shaped materialuntil a portion thereof sublimes Without fusing.

4. The process of making magnesia brick, which consists in vitrifyingmagnesia, reducing the vitrified material to powder, pressing it intoform, and subjecting it to a temperature' high enough to cause some ofthe magnesia to sublime.

Signed at New York, in the county ofNew York and State of New York, this4th day of NOEL POTTER.

August, A. D: 1903.

l. HENRY Witnesses:

, HERMAN SIEGEL,

.WM. OAPEL.

